<h2>Problem 118</h2>
<div style="color:#666;font-size:80%;">24 March 2006</div><br />
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<p>Using all of the digits 1 through 9 and concatenating them freely to form decimal integers, different sets can be formed. Interestingly with the set {2,5,47,89,631}, all of the elements belonging to it are prime.</p>
<p>How many distinct sets containing each of the digits one through nine exactly once contain only prime elements?</p>

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